Field of the Invention
The present invention relates to a solid-state imaging apparatus such as an electronic camera, and a driving method of the solid-state imaging apparatus.
Description of the Related Art
In an imaging apparatus provided with an XY-address scanning type of imaging element, a rolling shutter method is employed which controls a charge accumulation period of a photoelectric conversion element for every line by addressing. When moving images have been photographed by using this rolling shutter method under a fluorescent lamp, there is the case where unevenness in stripe along a row (hereafter referred to as flicker) appears in the image due to the influence of the periodic change of luminance by flicker frequency of the light source (for instance, frequency of 50 Hz or 60 Hz in commercial power supply) of the fluorescent lamp. For this reason, Japanese Patent Application Laid-Open No. 2011-176622 proposes an imaging apparatus which calculates the flicker frequency of a light source from the photographed image, and reduces the flicker based on the flicker frequency.
There is the case where the imaging apparatus according to Japanese Patent Application Laid-Open No. 2011-176622 cannot set the charge accumulation period at the integral multiple of the half cycle of the flicker frequency, in the case of moving images in which the frame rate is so high as the read-out time for one screen becomes shorter than the flicker cycle of the light source (for instance, in case of moving images of 1,000 fps). In this case, the flicker cannot be reduced.